Electric switch



Aug, 28, 1951 BADDOUR 2,565,643

ELECTRIC SWITCH Filed Oct. 15, 1947 3 Sheets-Sheet l g- 28, 1951 M. F. BADDOUR 2,565,643

ELECTRIC SWITCH Filed Oct. 15, 1947 3 Sheets-Sheet 2 ll u! ML 56. 6 94 ll 77 M J INVENTOR.

4 Mae/c: 54000; Y

Aug. 28, 1951 M. F. BADDOUR 2,565,643

ELECTRIC SWITCH Filed Oct. 15, 1947 3 Sheets-Sheet 5 70X 95 13 104 b I INVENTOR.

97 fiZvu/ficz' A 5190001 Patented Aug. 28, 1951 ELECTRIC SWITCH Maurice F. Baddour, Cleveland, Ohio, assignor to Designers for Industry, Inc., Cleveland, Ohio, a

corporation 01' Ohio Application October 15, 1947, Serial No. 780,059

18 Claims.

This invention relates to electric switches and, more particularly, to switches of the kind known as coaxial switches and which are used with socalled coaxial cables adapted to carry high-frequency electric current.

Switches of this general type are employed in radio apparatus, radar equipment and the like, and may be used in shifting a given circuit con- 'nection from one to another of a plurality of branch circuit connections. One example of such use of a switch of this type is where provision is made for shifting the connection for the coaxial lead-in cable of a radio apparatus from one antenna to another. The switches heretofore provided for use with coaxial cables have not been satisfactory because of the fact that signals from the unused branch circuit or antenna were frequently transmitted through the switch and produced interference or cross-talk in the wanted signals being received from the used branch circuit or antenna.

It is, accordingly, the principal object of the present invention to provide an improved con-' struction for electric switches used in high-frequency radio circuits, and the like, in which the reduction or attenuation of undesired signals will be achieved to a very high degree.

Another object of this invention is to provide an improved electric switch for high frequency radio circuits, and the like, in which means is provided for effectively blanking-oil or isolating the unused circuit connection or connections.

A further object is to provide an improved electric switch of the character mentioned in which a movable member or rotor shifts a contact member from one circuit connection to another in accordance with the circuit connection desired to be used, and in which dielectric medium is thereby brought into position to efiectively blank-oil or isolate the unused circuit connection or connections.

Still another object is to provide an electric switch of the type embodying a rotor having a passage containing a coaxial conductor and also having a contact member connected with such conductor and adapted for engagement with one of a group of spaced stationary contacts, and in which the rotor has peripheral openings containing dielectric medium and spaced apart so as to locate the dielectric medium in blanking-off or isolating relation to unused stationary contacts.

The invention can be further briefly summarized as consisting in certain novel combinations and arrangements of parts hereinafter described and particularly set out in the claims.

In the accompanying sheets of drawings,

Fig. 1 is a side elevation of an electric switch embodying the present invention;

Fig. 2 is a sectional view taken through the switch of Fig. 1 substantially as indicated by section line 22;

Fig. 3 is a view partially in elevation and partially in section showing the switch rotor on an enlarged scale and in detached relation;

Fig. 4 is a transverse sectional view on such enlarged scale and taken through the rotor as indicated by line 44 of Fig. 3;

Fig. 5 is a perspective view showing one of the stationary contacts;

Fig. 6 is an elevational view showing another switch embodying the present invention, portions of the housing of the switch being broken away;

Fig. '7 is a sectional view taken through the switch of Fig. 6 substantially as indicated by section line 'l-l;

Fig. 8 is an'elevational view showing the switch rotor in detached relation;

Fig. 9 is another view of the rotor in detached relation, but with portions of the rotor shown in section;

Fig. 10 is a sectional view taken transversely through the rotor, as indicated by line I 0-"! of Fig. 9;

Fig. 11 is an elevational view showing still another electric switch embodying the present invention;

Fig. 12 is a sectional view thereof taken on line l2-l2 of Fig. 11;

Fig. 13 is another elevational view of the switch but with portions of the switch housing broken away;

Fig. 14 is an elevational view of the switch rotor showing the same in detached relation and with portions of the rotor body broken away;

Fig. 15 is an end view of the rotor showing the same with portions of the rotor body broken away; and

Fig. 16 is an end view showing the rotor as seen from the opposite end.

In the embodiment of the invention illustrated in Figs. 1 and 2, a coaxial switch I0 is shown which comprises, in general, a switch housing H and a movable switch member or rotor l2 operable in such housing. The housing H can be of any desired shape, but is preferably polygonal so as to have substantially fiat outer faces and, for example, may be of a substantially square or cubical shape as shown in this instance. The housing is preferably formed of complemental housing sections Na and llb which are made of metal and are held in assembled relation by suitable connecting members or screws I3.

In the housing II, as here illustrated, the sections I Ia and I Ib have inter-fitting engagement by radial groove I9 extending around the annular periphery of subh chamber.

The switch housing II is provided with a plurality of spaced stationary contacts 26 with which the rotor I2 cooperates, as will be explained in greater detail hereinafter. The contacts 26 are shown in this instance as being three in number spaced 90 apart and comprising a main contact 20a and two branch contacts 20b and 260. The contact 26a can be conveniently it may be connected with a lead-in conductor or cable (not shown) extending to a radio apparatus, and the contacts 26b and 200 can be conveniently referred to as branch contacts because they may be connected with conductors or cables (not shown) leading to two different antennae. As will be explained more in detail hereinafter, the switch III provides an improved device by which one or the other of the branch contacts 26b and 260 can be connected with the main contact 20a. In the switch as illustrated in' Fig. l, the rotor I2 is shown in the position to connect the branch referred to as the main or supply contact because contact 20b with the main contact 20a and at which time the branch contact 200 represents an unused circuit connection.

The contacts 20 can all be identical in form and may be of any suitable construction. In this instance, these contacts are shown as each comprising a pair of spaced-apart spring fingers 2Ia and 2Ib carried by the inner end of a conductor member 22 and located so as to extend toward or into the rotor chamber I8 on opposite sides of the radial groove I9. The conductors 22 for the contacts 20a, 26b and 260 extend in coaxial relation in metal connector members 23, 24 and 25 in which these conductors are mountedby means of bodies 26 of suitable electrical insulating ma-' terial such as polystyrene. The bodies 26 can be retained in the connector members as by means of the inwardly deflected locking elementsZI.

The contacts 26a, 26b and 260 are mounted on the housing II by means of the connector members 23, 24 and 25 which engage the fiat side faces 23a, 24a and 25a of the housing section IIa. These connector members can be of an identical construction, each comprising a tubular portion 28 having an axial passage or chamber 28a in which the electrical insulating body 26 is mounted and a plate portion 29 at the irmer end thereof adapted to be clamped against one of the fiat side faces of the housing by means of the screws 36. The tubular portion 28 of the connector members is provided at its outer end with an externally threaded sleeve portion 3 I, to which: a coaxial cable (not shown) leading to an antenna or'to a radio apparatus can be connected. The outer end of v the conductor 22 of the connector'members extends into the sleeve portion 3| in the form of a resilient terminal element or contact 32 adapted for releasable connection with the inner conductor of the coaxial cables which would be attached to the connectormembers.

In the switch III, as shown in Fig. 1. the connector members 24 and 25 carrying the branch contacts 26b and 200 have their plate pqjftions 29 in engagement with the two opposed "flat side faces 24a and 25a of the housing II, and the connector member 23 which carries the contact 26a has its plate portion 29 in engagement with the flat face 23a which lies between the faces 24a and 25a. At the locations of the flat side faces 23a, 24a and 25a the housing section Ila has openings 23b, 24b and 25?) extending inwardly substantially normal to the planes of these flat faces and communicating with the switch chamber I8. When the connector members are mounted on the housing the contacts 26a, 20b and 200 thereof extend into or through the openings 23b, 24b and 251) respectively.

The movable switch member or rotor I2 is here shown as comprising a substantially cylindrical body having substantially aligned oppositely extending shaft portions 31 and 38 which are journaled in aligned openings 39 and 46 of the housing sections Ma and I II). The rotor I2 has a curved passage 4I extending through the body thereof and includes a conductor 42 located in such passage and extending coaxially thereof. The rotor passage 4|, as here shown, is a curved passage whose outer ends terminate in peripheral openings 43 and 44 of the rotor which are spaced apart an angular distance of to correspond with the angular spacing between the contacts 20a and 26b and between the contacts 26a and 260. The conductor 42 is of curved shape to correspond with the passage M and is mounted in this passage by means of a body 45 of electrical insulating material such as polystyrene which substantially fills the passage and is preferably molded in place therein.

The rotor I2 also includes a substantially radially extending peripheral flange 46. The peripheral openings 43 and 44 defining the ends of the curved rotor passage 4| include recesses or interruptions 43a and 44a in this peripheral flange, and the insulating body 45 includes inte ral extensions or radial flange portions 41 and 46 which fill the interruptions 43a and 44a. The extensions 41 and 48 have an axial thickness and radial length corresponding with the axial thickness and radial length of the peripheral flange 46 so as to form smooth and flush continuations of this flange.

The rotor I2 also includes contact members 49 and 56 which are connected with the ends of the curved conductor 42 and are mounted in the interruptions 43a and 44a of the peripheral flange 46 but are insulated from the adjacent portions of the flange by the. integral extensions 41 and 48 of the insulating body 45. The contact members 49 and 50 may be separately formed members which are connected with the ends of the conductor 42, or can be members formed directly on the conductor at the ends thereof. The contact members 49 and 50 have the same axial thickness and radial height as the flange 46 and the insulating extensions 41 and 48 so as to lie in a smooth and flush relationship with the flange and the insulating extensions.

When the rotor I2 is mounted in the chamber I8 of the switch housing II, as shown in Figs. 1 and 2, the peripheral flange 46 extends into the radial groove I9 of the housing and is embraced by the pairs of resilient fingers 23a and 23b of the stationary main and branch contacts 20a, 26b and 260. Fig. 1 of the drawings shows the rotor I2 in the position in which the curved conductor 42 connects the main contact 26a with the branch contact 20b and at which time the branch contact 200 is the unused contact. When the rotor is in this position the resilient fingers Ila and Nb of the contact 20a engage opposite sides of the contact member 49 of the rotor and the resilient fingers of the contact 20b engage opposite sides of the contact member 50. When the rotor is moved through 90 in a clockwise direction from the position shown in Fig. 1, the curved conductor 42 will connect the main contact 20a with the branch contact 200 and the contact 20b will then be the unused contact.

The rotor I2 can be constructed by any appropriate manufacturing operations and, if desired, the body of the rotor may comprise two complemental sections 5| and 52 which are held in assembled relation by means of suitable fasteners or rivets 53 extending therethrough. The shaft portions 31 and 38 can be in the form ofintegral extensions carried by the rotor sections 5| and 52. The curved passage 4| can be obtained by providing the rotor sections 5| and 52 with curved complemental grooves which are milled or otherwise formed in the adjacent faces thereof and which cooperate to define the curved passage when the rotor sections are assembled in face to face relation.

In constructing the rotor I! it is desirable to make the sections 5| and 52 of an initial diameter, at least as great as the final diameter desired for the radial flange 46 and to turn or otherwise machine these sections down to substantially the desired final diameter so as to leave the radial flange 46 on the rotor body. It is also desirable to mold the end portions of the insulating body 45 so as to fill the curved passage 4| out to the peripheral surface of the initial rotor diameter and to machine away the excess portions of the insulating material leaving the integral extension portions 41 and 46 which will then conform in radial height and axial thickness with the flange 46.

As explained in the early portion of this specification, an important part of the present invention is in providing means for effectively blankingoff or isolating the unused contacts of the switch housing so as to obtain a desired attenuation of unwanted signals and thus eliminate interference or cross-talk. This is accomplished in the switch It by constructing the rotor l8 so that it will provide dielectric medium in blanking-off or isolating relation to the unused contact of the switch housing. For this purpose the body of the rotor 18 is provided with a second pair of peripheral openings or recesses 55 and 56 which are spaced apart to correspond with the spacing of the contact members 49 and 50, that is to say, an angular distance of 90. The peripheral openings 55 and 56 are also located on the rotor so that when the contact members 49 and 50 are engaged by two of the contacts of the switch housing, one of the second pair of peripheral openings will be located in front of and in blanking-oil! or isolating relation to the unused branch contact of the switch housing.

The peripheral openings 55 and 56 include outwardly extending interruptions 55a and 56a in the radial flange 46, as shown in Fig. 4. A second passage 51 formed in the body of the rotor connects the openings 55 and 56 adjacent the inner ends thereof. The peripheral openings 55 and 56 are here shown as containing a solid plastic electrical insulating material, such as polystyrene, which is molded in place therein so as to substantially fill these openings and form insulating bodies 58 and 59 therein. This insulating material also forms a connecting stem 60 for the bodies 58 and 59 and which substantially fills the passage 51. The insulating bodies 58 and 59 include integral exten'sion portions 58a and 59a which fill the interruptions a and 56a of the radial flange 46 and which extensions have am axial thickness and radial height corresponding with the flange 46 so that these extensions form smooth and flush continuations of the flange. The insulating bodies 58 and 6 are preferably molded in place in the peripheral openings 55 and 56 of the rotor prior to the above described machining operation by which the rotor is turned down to its desired final diameter so that the extension portions 58a and 59a. will be left in the interruptions 55a and 55a of the radial flange 46.

When the switch rotor I2 is in the position illustrated in Fig. 1, the insulating body 56 will lie opposite the unused branch contact 200 and will serve to blank-off this unused contact and effectively prevent interference or crosstalk. While the insulating body 58 occupies such a blanking-off position the spring fingers lie and 2th of the contact 200 will engage opposite sides of the integral extension 58a of the insulating body and will thus be entirely disconnected from all metal portions of the rotor body. Similarly, when the switch rotor I2 is shifted to connect the branch contact 200 with the main contact 20a, the insulating body 58 and its integral extension 59a will occupy a blanking-off position with respect to the then unused contact 20b.

The above described blanking-off of the unused contact can also be obtained by constructing the switch in So that the peripheral openings 55 and 56 of the rotor l8 are left entirely empty and contain only air as a dielectric medium or electric insulating material. In this case the interruptions 55a and 56a of the peripheral flange 46 contain only air as a dielectric medium or insulating material. Although satisfactory results can be obtained by the use of air as the dielectric medium or insulating material for accomplishing the blanking-off function just-explained above, it is usually desirable to provide a solid plastic insulating material in the peripheral openings 55 and 56 and in the flange interruptions 55a and 56a because the integral extensions 56a and 59a and the portions 41 and 48 of the body 45 all form smooth continuations of the radial flange 46 on which the spring fingers 23a and 23b of the housing contacts can operate smoothly during arcuate shifting of the rotor.

Figs. 6 and 7 of the drawings show another coaxial switch 63 which comprises, in general, a metal switch housing 64 and a rotor 65 operable therein. The housing 64 carries a main contact 66 and a pair of branch contacts 61 and 68, each of the latter being spaced a given arcuate distance from the main contact, for example, a distance of as shown in this instance.

The contacts 66, 61 and 68 can be of a construction similar to that described above for the contacts 20a, 20b and 200 of Fig. l and can be carried in a similar manner by suitable connector members 69, 10 and H.

The housing 64 is here shown as having the shape of a pentagon and the connector members 69, 10 and 1| are mounted on the flat side faces 12, 13 and 14. The housing has openings Ila sulating body 8|.

13a and 14a therein at the flat faces 12, 13 and 18 which communicate with a rotor chamber 15 and into which portions of the connector members 88, 18 and H extend. The rotor chamber 15 has a peripherally extending radial groove 15a and when the connector members are mounted on the flat side faces oi! the housing, the contacts 88, 81 and 88 extend toward or into the rotor chamber and the spring fingers 2Ia. and 2Ib of the contacts straddle this groove, as shown in Fig. 'l.

The rotor 85 comprises a metal rotor body 85a having axially aligned shaft extensions 18a. and 18b thereon which are journaled in aligned openings of the complemental housing sections 84a and 84b. The rotor 85 includes a conductor 11 extending therethrough and contact members 18 and 18 at the ends of the conductor and which are adapted to be engaged by the contacts 88 and 81, or 88 and 88 of the switch housing, depending upon the position of the rotor in the rotor chamber. The conductor 11 is mounted in the rotor body 8511 by providing the latter with a passage 88 in which the conductor is located in coaxial relation. The conductor 11 is mounted in the passage 88 by means of a body M of suitable insulating material, such as polystyrene, which is molded in place in the passage. The rotor 85 also includes a substantially radial peripheral flange 82 and a pair of peripheral openings 83 and 84 forming the ends of the passage 88. The openings 83 and 84 are spaced apart an angular distance of 150 to correspond with the spacing of branch contacts 81 and 88 from the main contact 88. The flange 82 has interruptions 83a and 84a formed by the peripheral openings 83 and 84 and the contact membars 18 and 19 of the rotor are located in these interruptions, but are insulated from the adjacent metallic portions Of the radial flange by the integral extensions 8Ia and 8Ib oi the in- The contact members 18 and 18 and the insulating extensions 8Ia and 8Ib form smooth and flush continuations of the radial flange 82 in the same mannerand for the same purpose as has been explained in detail above in connection with the switch I8.

The rotor 85 also has a second pair of peripheral openings 88 and 81, and the radial flange 82 has interruptions 88a and 81a therein at the locations of the peripheral openings 88 and 81. The peripheral openings 88 and 81 are here shown as containing a dielectric medium, preferably in the form of bodies 88 and 88 of molded plastic insulating material, such as polystyrene, A second passage 88 formed in the rotor connects the peripheral openings 81 and 88 and may contain a stem SI of insulating material which joins the bodies 88 and 88. The insulating bodies 88 and 88 may contain integral extension portions which fill the interruptions 88a andv 81a or, as here shown, .these interruptions can be left open so as to contain only air as a dielectric medium. The openings and passages of the rotor 85' can be drilled or otherwise formed therein.

When the switch rotor 85 occupies the position shown in Fig. 6, the conductor" connects the blanked-o8? or isolated by the insulating body 88 which is then in register with this contact. When the switch member is rotated through an angular distance of 150 in a counter-clockwise direction from the position shown in Fig. 6, the conductor 11 will then connect the branch contact 81 with the main contact 88. Atthis time the spring flngers 2Ia and 2") of the contact 88 will engage opposite sides of the contact member 18 and the spring fingers of the branch contact 81 will engage opposite sides of the contact member 18. While the switch rotor is in the latter position the branch contact 88 is the unused contact and will be efiectively blanked-off or isolated by the insulating body 88 which is then in registering relation with this contact.

The rotor 85 of the switch 83 can be shifted from one to the other of the two positions just described above by arcuate movement applied thereto through the crank 82 which is here shown on the outer end of the shaft portion 18b. The rotor can be releasably held in either of the desired positions by suitable detent means which is here shown as comprising a spring-pressed ball 83 carried by the switch housing 84 and a pair of appropriately spaced recesses 84 formed in the rotor and adapted to be engaged by such ball. Reverting to the switch l8, it should also be explained that the rotor I2 thereof can be releasably retained in either of the desired positions by suitable detent means similar to that illustrated in the switch of Figs. 6 and 7.

Figs. 11 and 12 show another coaxial switch 85 embodying the present invention and comprising, in general, a metal switch housing 88 and a rotor 81 operable therein. The housing 88 is here shown as being hexagonal in shape and having arcuately spaced branch contacts 88 located therein opposite the respective flat sides 88a of the hexagon. The contacts 88 are carried by connector members 88 and both the contacts and the connector mgmbers can be of a construction similar to that illustrated in the switch I8 of Figs. 1 and 2.

The rotor 81 comprises a rotor body 81a which may be made of cast metal and which has axially aligned shaft portions 91b and 810 rotatably mounted in complemental sections 881) and 880 of the housing 88. The rotor 81 also includes a conductor I88 and a contact member ml which is connected with one end of the conductor and is adapted to be engaged by one of-the contacts 88 of the switch housing. The rotor is provided with a passage I82 in which the conductor I88 is located in coaxial relation to such passage. The rotor 81 differs from the rotor I8 of Figs. 1 and 2 in that the curved passage I82 has one end thereof at the periphery of the rotor, as indicated by the peripheral opening I83, and its other end in concentric relation to the axis of the rotor as represented by the opening I84. The conductor I88 is mounted in the curved passage I82 by a body of suitable electrical insulating material I 85, such as a body of polystyrene molded in place therein. The curved passage I82 can be cored or otherwise formed in the rotor 81.

In addition to the arcuately spaced stationary branch contacts 88 of the switch housing, as mentioned above, the housing is also provided with a main contact or terminal I88 which is in the form of a hollow contact or sleeve into which the end portion I81 of the conductor I88 extends. The contact I88 is carried by a connector member I88 which is mounted on the switchhousin in coaxial relation to the rotor 81. The contact 9 I is mounted in the connector member I08 by means of the insulating body I09.

The rotor 91 also includes a substantially radially extending peripheral flange H through which the opening I03 of the rotor passage I02 extends, as indicated by the interruption III (see Fig. 16). The contact member IIII of the rotor is located in the interruption III and is adapted to be engaged by one of the contacts 98' of the switch housing depending upon the angular position selected for the rotor in the housing. In Fig. 11 the rotor 91 is shown in the position in which the contact member IIII is engaged by the branch contact 98a of the housing and at this time all of the remaining branch contacts 98 are unused contacts. When the rotor is shifted in a counterclockwise direction through increments of 60, the contact member IIII will engage each of the other branch contacts of the housing in succession and during such movement of the rotor the contact member III'I rotates in the contact sleeve I06.

As shown in Fig. 15 rotor 91 is provided with other peripheral openings H2 which are spaced therearound at 60 intervals to correspond with the spacing of the branch contacts 98 of the switch housing. The peripheral openings I I2 extend through the radial flange H0 of the rotor and form gaps or interruptions H3 therein. As here shown, the peripheral openings H2 contain dielectric medium, preferably bodies H4 of suitable solid plastic insulating material such as polystyrene and, in this instance, these bodies are molded in place therein. The insulating bodies I II include integral extensions IMa which fill the interruptions H3 of the rotor flange H0. These integral extensions have a radial height and axial thickness such that they form smooth and flush continuations of the radial flange I III. For locking the insulating bodies III in the peripheral openings H2, the latter are preferably provided with diverging angular extensions H5 at their -inner ends into which portions of the insulating bodies extend.

When the rotor 91 occupies a position with the contact member III in engagement with one of the housing contacts, such as the contact 98a as shown in Fig. 11, the insulating bodies I I4 will lie opposite the remaining five branch contacts 98 of the housing and will effectively blank-off or isolate all of these unused contacts. While'the insulating bodies I II are in this blanking-off or isolating relation to the unused contacts 98, the spring fingers 2 Id and 2 lb of the unused contacts will engage opposite sides of the extensions H4a of the insulating bodies so as to be entirely disconnected from the metallic portions of the rotor.

The rotor 91 can be actuated by rotary or stepby-step arcuate movement imparted thereto through the shaft member 910, and the positioning of the contact member IIII of the rotor in the switch housing in the desired relation to the branch contacts 98 can be accomplished by suitable detent means, such as the ratchet wheel I I6 and the spring pressed pawl I I! cooperating therewith.

From the foregoing description and the accompanying drawings it will now be readily understood that the present invention provides an improved construction for electric switches, and particularly for electric switches of the so-called o0- axial type. It will now also be seen that the improved construction provided by this invention produces a desired attenuation of undesired signals by effectively blanking-off or isolating the 10 unused switch contacts by means of dielectric medium.

In further explaining the novel characteristics and important advantages of applicants coaxial switch it is pointed out that coaxial switches have been proposed heretofore in which a metal rotor operable in a metal housing carries a conductor which is insulated from the metal rotor and, by movement of the rotor, is adapted to be positioned so as to connect the contact of a main energy channel with the contact of a desired or used branch channel. In the prior constructions of this type the contacts of the unused branch channels were grounded on the rotor for the purpose of eliminating cross-talk but this has not proved satisfactory because the stray energy thus transmitted to the rotor by direct contact did not pass readily to the housing from all points of the rotor. When the fit of the rotor in the housing was made close enough for the stray energy of the rotor to be transmitted to the housing by grounding, it was found by actual tests that the rotor would bind and jam in the housing.

The coaxial switch herein disclosed embodies three predominantly important structural features, one being the provision of the dielectric pockets in the rotor which isolate the unused contacts of the branch channels and prevent the direct transfer of stray energy between such unused channels and the rotor, and second, the fact that the rotor is of a size and shape to fill the chamber of the switch housing with a small clearance therebetween providing a capacitance coupling between the rotor and housing, and third, the provision of a radial flange on the rotor with which the contacts of the housing have smooth running engagement. In a switch of this construction the stray energy transmitted from the unused channels to the rotor by condenser action therebetween will be small in amount and will be bypassed to the housing by virtue of the capacitance coupling between the rotor and the housing. Since the amount of this stray energy is small it will produce very little cross-talk effect and the coupling of the rotor to the housing can be satisfactorily obtained without using 'such a close fit therebetween as would prevent free turning of the rotor. When a solid dielectric is used in the rotor pockets for isolating the unused channels the rotor surface or flange remains continuous, as previously pointed out herein, and the contacts of the channels have smooth running engagement with the rotor.

Although the improved switch construction provided by this invention has been illustrated and described in considerable detail, it will be understood, of course, that the invention is not to be regarded as being limited correspondingly in scope, but includes all changes and modifications coming within the scope of the claims hereof.

Having thusdescribed my invention, I claim:

1'. A switch of the character described comprising, a housing having a chamber therein, contacts carried by said housing disposed adjacent the periphery of said chamber and spaced apart arcuately thereof, a rotor arcuately movable in said chamber and being of a size and shape to substantially fill said chamber, and a contact member carried by said rotor and adapted for selective engagement with the contacts of said housing by the arcuate movement of the rotor in said chamber, said rotor including portions formed of solid dielectric material and spaced apart so as to lie in front of and isolate those housing contacts which are not engaged by the I 11. contact member of the rotor at any position the latter in which the said contact member is engaged with a housing contact.

2. In an electric switch of the coaxial type, 'a switch body having electrically insulated contacts arcuately spaced apart a given angular distance, a movable switch member having a group of peripheral openings angularly spaced apart to correspond substantially with the given angular spacing of said contacts and having a passage communicating with one of said peripheral openings, a conductor disposed in said passage and carried by said switch member, a contact member connected with. said conductor and located at said one opening for selective engagement with any one of said arcuately spaced contacts and being shiftable from one of the arcuately spaced contacts to another by movement of the switch member, electrical insulating material mounting said conductor in said passage coaxially thereof, other openings of said group containing bodies of solid dielectric medium cooperating with the unused contacts of said switch body at any given position of said switch member to isolate such unused contacts.

3. In an electric switch of the coaxial type. a switch body having a chamber therein, electrically insulated contacts supported by said body with their inner ends adjacent the periphery of said chamber and arcuately spaced apart agiven angular distance, a switch member movably supported in said chamber, the said switch member being of a size and shape to substantially fill said chamber and having a group of peripheral openings angularly spaced apart to correspond substantially with the given angular spacing of said contacts, the said member also having a passage communicating with one of. said peripheral openings, a

' conductor disposed in said passage and carried by said switch member, a contact member connected with said conductor and located at said one opening for selective engagement with one of said arcuately spaced contacts of said body and being shiftable from one of the arcuately spaced contacts to another by movement of the switch member, a solid plastic electric insulating material mounting said conductor in said passage coaxially thereof, and a solid plastic electric insulating material in the other openings of said group for cooperation with the unused contacts of said switch body at any given position of said switch member to isolate such unused contacts.

4. In an electric switch, a switch body having electrically insulated contacts arcuately spaced apart a given angular distance, a movable switch member having a group of peripheral openings angularly spaced apart to correspond substantially with the given angular spacing of said contacts and a passage interconnecting a pair of said peripheral openings, a conductor disposed in said passage and carried by said switch member, contact members connected with the ends of said conductor and located at the openings of said pair for engagement with contacts of said switch body, electrical insulating material mounting said conductor in said passage, and solid dielectric medium in the other openings of said group for isolating the unused contacts of said switch body.

5. In an electric switch, a switch body having a chamber therein, a plurality of arcuately spaced contacts supported by said body with the inner ends of said contacts adjacent the periphery of said chamber, a rotor in said chamber and supported for rotary movement therein, the said rotor including a substantially radial circumferential flange thereon, the said rotor also having a group of peripheral openings therein interrupting said flange at points corresponding substantially with the arcuate spacing of the contacts of said switch body, and there being a passage in said rotor communicating with one of said peripheral openings, a conductor in said passage, a contact member connected with said conductor and located at said one peripheral opening for selective engagement with any one of the contacts of said switch body, electrical insulating material mounting said conductor in said passage and mounting said contact member in the interruption of said flange, and solid dielectric medium in other openings of said group for cooperating with the unused contacts of said switch body at any given position of said rotor to thereby isolate such unused contacts.

6. In an electric switch, a switch body having a chamber therein, a plurality of arcuately spaced contacts supported by said body with the inner ends of said contacts adjacent the periphery of said chamber, a rotor in said chamber and supported for rotary movement therein, the said rotor including a substantially radial circumferential flange thereon, said rotor having a group of peripheral openings therein interrupting said flange at points corresponding substantially with the arcuate spacing of the contacts of said switch body and there being a passage in said rotor communicating with one of said peripheral openings, a conductor in said passage, a contact member connected with said conductor and located at said one peripheral opening for selective engagement with any one of the contacts of said switch body, solid plastic electrical insulating material mounting said conductor in said passage and said contact member in the interruption of said flange, and bodies of solid plastic electrical insulating material filling the other openings of said group and the flange interruptions corresponding with such other openings, the said contact member and portions of said insulating material forming smooth and flush continuations of said flange whereby the unused contacts in said switch body at any given position of said rotor have solid dielectric material cooperating therewith thereby isolating such unused contacts.

7. In an electric switch, a switch body having a chamber therein, a plurality of arcuately spaced contacts supported by said body with the inner ends of said contacts adjacent the periphery of said chamber, a rotor in said chamber and supported for rotary movement therein, the said rotor including a substantially radial circumferential flange thereon, the said rotor having a group of peripheral openings therein interrupting said flange at points corresponding substantially with the arcuate spacing of the contacts of said switch body and there being a passage extending through said rotor and connecting a pair of said peripheral openings, contact members located in the flange interruptions at said pair of peripheral openings for engagement with a pair of the contacts of said switch body, a conductor disposed in said passage and connecting said contact members, solid plastic electrical insulating material mounting said conductor in said passage and said contact'members in said flange interruptions, and bodies of said solid plastic insulating material filling the other openings of said group, whereby the unused contacts of said switch body at any operative position of said rotor have solid insulating material cooperating therewith thereby isolating such unused contacts.

8. In an electric switch, a switch body having a chamber therein, a plurality of arcuately spaced contacts supported by said body with the inner ends of said contacts adjacent the periphery of said chamber, a rotor in said chamber and supported for rotary movement therein, the said rotor having peripheral openings therein at spaced points corresponding substantially with the arcuate spacing of the contacts of said switch body, said rotor also having a passage extending therethrough and connecting a pair of said peripheral openings and a second passage extending therethrough and connecting a second pair of said peripheral openings, contact members located at the first pair of said peripheral openings and adapted for engagement with a pair of the arcuately spaced contacts of said switch body, a conductor extending coaxially of the first passage and connecting said contact members, solid plastic electrical insulating material mounting said conductor in said flrst passage, bodies of solid plastic electrical insulating material mounted in the second pair of peripheral openings and serving to isolate unused contacts of said switch body, and a stem extending axially of said second passage and connecting said bodies of plastic insulating material.

9. In an electric switch, a switch body having a chamber therein, a plurality of arcuately spaced contacts supported by said body with the inner ends of said contacts adjacent the periphery of said chamber, a rotor in said chamher and supported for rotary movement therein, the said rotor being of a size and shape to substantially fill said chamber and including a substantially radial circumferential flange there: on, the said rotor having peripheral openings therein interrupting said flange at points corresponding substantially with the arcuate spacing of the contacts of said switch body, said rotor also having a passage extending therethrough and connecting a pair of said peripheral openings and a second passage extending therethrough and connecting a second pair of said peripheral openings, contact members located in the flange interruptions corresponding with the first pair of said peripheral openings and adapted for engagement with a pair of the arcuately spaced contacts of said switch body, a conductor extending coaxially of the first passage and connecting said contact members, solid plastic electrical insulating material mounting said conductor in said first passage and said contact members in said corresponding interruptions of said flange, bodies of solid plastic electrical insulating material mounted in the second pair of peripheral openings for cooperation with unused contacts of said switch body to isolate the latter, and connecting means extending axially in said second passage and connecting said bodies.

10. In an electric switch, a switch body having electrically insulated arcuately spaced contacts, a rotor operable in said switch body and including a substantially radial circumferential flange thereon, the contacts of said switch body comprising pairs of resilient contact fingers adapted to embrace said flange and engage opposite sides thereof, said rotor also having peripheral openings therein interrupting said flange at points corresponding substantially with the arcuate spacing of the contacts of said switch body and a, passage extending into the rotor from one of said peripheral openings, a conductor in said passage, a contact member connected with said conductor and located in the flange interruption corresponding with one of said peripheral openings, and solid electrical insulating ma terial located in said passage and peripheral openings of the rotor including the interruptions of said flange with the portions of the insulating. material located in the said interruptions forming smooth and flush continuations of said flange, the insulating material in said passage and said one peripheral opening serving to insulate said conductor and contact member from the rotor and the insulating material in other peripheral openings serving to isolate unused contacts of the switch housing.

11. In an electric switch, a switch body having electrically insulated arcuately spaced contacts, a rotor operable in said switch body and including a substantially radial circumferential flange thereon, the contacts of said switch body comprising pairs of resilient contact fingers adapted to embrace said flange and engage opposite sides thereof, said rotor also having peripheral openings therein interrupting said flange at points corresponding substantially with the arcuate spacing of the contacts of said switch body, a passage in said rotor connecting one pair of said peripheral openings and a second passage in the rotor connecting a second pair of said peripheral openings, a conductor in the first rotor passage, contact members connected with said conductor and located in the flange interruptions corresponding with said one pair of peripheral openings, solid plastic electrical insulating material in the first rotor passage and in the flange interruptions corresponding therewith and serving to insulate said conductor and contact members from the rotor, bodies of solid plastic electrical insulating material in said second pair of peripheral openings and in the flange interruptions corresponding therewith and cooperating with unused contacts of the switch housing to isolate the unused contacts, and a stem of said insulating material in said second passage for connecting said bodies, said contact members and the insulating material in said interruptions forming smooth and flush continuations of said flange.

12. In a coaxial switch for use with coaxial conductors adapted to carry high-frequency current, a switch housing having a main contact and a pair of branch contacts spaced a given angular distance on opposite sides of said main contact, a rotor operable in said housing and having pairs of peripheral openings spaced apart to correspond with said given angular distance, passages extending through said rotor and connecting the pairs of said peripheral openings, contact members located in one pair of said peripheral openings and adapted to be engaged by said main contact and one of said branch contacts, a conductor extending coaxially in one of said passages and connecting said pair of contact members, solid plastic electrical insulating material in said one passage insulating said contact members and conductor from said rotor and maintaining said conductor in coaxial relation in said passage, bodies of solid plastic electrical insulating material in the other pair of peripheral openings, and a stem of said insulating material in the other passage of the rotor and connecting said bodies, whereby operation of said rotor to a position such that said pair of contact members engages said main contact and one of said branch contacts also positions one of said bodies of solid insulating material of the rotor to cooperate with and isolate the unused branch contact of said housing.

13. A switch as defined in claim 12 in which the solid plastic insulating material is molded in place in the rotor.

14. In an electric switch, a polygonal switch housing having substantially fiat sides corresponding with the sides of said polygon, said housing having a chamber therein and openings extending inwardly from said flat sides and communicating with said chamber, connector members mounted on said housing at said flat sides, contacts carried by said connector members and projecting inwardly through said openings, a rotor operable in said chamber and including a radially extending circumferential flange, the said rotor having a group of peripheral openings therein and extending through said flange with the said openings angularly spaced apart to correspond substantially with the angular spacing of the contacts of said switch housing, said rotor also having a passage therein communicating with one of said peripheral openings, a conductor disposed in said passage, a contact member connected with said conductor and located at said one opening in said flange for selective engagement with any one of said arcuately spaced contacts by arcuate movement of the rotor, electrical insulating material mounting said conductor in said passage coaxially thereof, and solid electrical insulating material in the other openings of said rotor for cooperation with unused contacts of said switch housing at any setting of said rotor to thereby isolate the said unused contacts, the said contact member and the insulating material in said openings substantially filling the latter so as to provide a smooth continuous sur-' face on said flange.

15. In an electric switch of the coaxial type, a switch body having a chamber therein and electrically insulated contacts spaced arcuately around said chamber, a rotor operable in said chamber and having a substantially radial continuous circumferential flange thereon, the contacts of said switch body comprising pairs of resilient contact fingers adapted to embrace said flange and engage opposite sides thereof, the said rotor having a pair of peripheral openings therein interrupting said flange at points corresponding substantially with the arcuate spacing of the contacts of said switch body and a passage extending through the rotor and connecting said pair of peripheral openings, a conductor in said passage, flat sided contact members connected with said conductor and located in said flange interruptions and lying substantially in the plane of said flange, and solid dielectric material in said passage mounting said conductor coaxially therein with portions of said dielectric material extending into said flange interruptions for mounting said contact members in the latter, the flat sides of said contact members and said portions of the solid dielectric material forming smooth flush portions of the side faces of said continuous flange.

16. The combination as defined in claim 15 and wherein the said rotor has other openings therein extending through the flange thereof and angularly spaced in accordance with the angular spacing of the contacts on said switch body, and solid dielectric material filling said other, openings in said rotor and its flange and forming smooth flush continuations of the surface of said flange.

,therebetween, said rotor having peripheral openings spaced apart in the direction of rotor movement to correspond substantiall with the spacing of said stationary contacts and also havin a passage extending thereinto from one of said openings, a conductor disposed in said passage and including a rotor contact located adjacent the periphery of the rotor for selective engagement with stationary contacts of said housing, insulating means mounting said conductor in said passage coaxially thereof, other peripheral openings of said rotor forming pockets which will be respectively positioned in front of all the unused stationary contacts when said rotor contact is in engagement with a selected one of said stationary contacts, and dielectric medium in said pockets for simultaneously isolating all of the unused contacts from direct electrical connection with said rotor.

18. In an electric switch of the coaxial type, a metal housing having a substantially cylindrical chamber therein, a plurality of spaced electrically insulated stationary contacts supported by said housing with their inner ends disposed adjacent the periphery of saidchamber, a substantially cylindrical metal rotor mounted for rotation in said housing and being of a size to substantially fill said chamber to produce capacitance coupling therebetween, said rotor having peripheral openings spaced apart in the direction of rotor movement to correspond substantially with the spacing of said stationary contacts and also having a passage extending thereinto from one of said openings, a conductor disposed in said passage and including a rotor contact located adjacent the periphery of the rotor for selective engagement with stationary contacts of said housing, insulating means mounting said conductor in said passage coaxially thereof, other peripheral openings of said rotor forming pockets which will be respectively positioned in front of all the unused stationary contacts when said rotor contact is in engagement with a selected one of said stationary contacts, and solid dielectric medium substantially filling said pockets for simultaneously isolating all of the unused contacts from direct electrical connection with said rotor.

MAURICE F. BADDOUR. I

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

